At the Crossroads of Infinities is a story about the struggle of ideas out of which the modern physical picture of the world was born. Can anything move faster than light? Is the uni­ verse finite or infinite? Is time revers­ible? What lies at the basis of the realities which we perceive as space, time or matter? These are the questions taken up in this book. And more, for it also tells of the roads of know­ ledge, of the way man has probed the mysteries of the infinitely large and infinitely small, yet at root in­tegral world.